By default Serna does not show the top-level XSLT parameters in the XSLT Parameter Set Dialog (see XSLT Parameter Sets), because typical stylesheet contains many parameters irrelevant to the end user.
To make these parameters visible, the following Serna extension attributes should be added to their stylesheet definitions:
Do not forget to declare the extension namespace xmlns:xse="http://syntext.com/Extensions/XSLT-1.0" in the top element of the stylesheet.
This attribute may have the following values: numeric and string, depending on the semantics of the parameter. This attribute serves as a hint on the semantics to the user in the dialog, and allows user not to specify quotes for the string parameters. You must specify this attribute in order that it appears in the XSLT Parameter Sets Dialog.
This attribute provides a human-readable annotation to the parameter, and shows up in the XSLT Parameter Sets Dialog hints. This attribute is optional.
XSLT Parameters which are Result Tree Fragments are not supported. Always use select attribute, and do not use RTF form:
<xsl:param name="nextWord" xse:type="string" select="'Next'"/>
But not:
<xsl:param name="nextWord" xse:type="string">'Next'</xsl:param>